Prepare subtitles for a cinema DCP on Mac

Find out what is already in the booth

Suppose a festival has ingested your film about a ferry crossing. It now needs Dutch subtitles visible to everyone. Ask the projectionist for the Composition Playlist (CPL) name or identifier for the exact version they hold, and ask the mastering operator for its matching reference movie. Two cuts can have the same title and runtime but different dialogue under the final shot.

Confirm that the request is for open subtitles on the cinema screen. Closed captions go to a compatible personal display and need their own delivery and device check. Agree which party will build the digital cinema package (DCP), which subtitle input they accept, and who signs off in the booth. Use only a film and translation cleared for this screening; permission to review a screener privately does not by itself authorize a public subtitled version.

Send an SRT with two cues the operator can recognize

On an Apple Silicon Mac, open the approved reference movie in Polyglot and transcribe it locally after model setup. Check the source dialogue against the movie, then translate the reviewed track into Dutch if needed. If the translator has supplied an SRT, import a copy and attach that same reference for playback. Keep the approved original. Have a fluent reviewer compare the Dutch text with the original dialogue, especially place names, signs read aloud and remarks made off screen.

Give the operator one reviewed SRT per requested language, the matching composition identifier, the reference filename, and the time origin. For example, note that the Dutch line “De laatste pont” starts as the deckhand lifts the chain, twelve seconds from the start of the supplied movie. Identify another cue near the end by its exact words and action. Those two anchors let the operator spot a different leader at the start or a speed change that only becomes obvious later.

Decide whether the cinema needs one package or two

Polyglot exports the subtitle text and timings. The mastering operator makes the cinema package. DCP-o-matic accepts SubRip text and can build a Version File (VF) that adds subtitles while referring back to the existing package for picture and sound. The booth needs both that original package and its matching VF available. Ask it to select the subtitled composition for playback; selecting the original can give a perfectly good picture with no Dutch words.

If the venue needs one self-contained delivery, the operator can instead master a complete DCP with projector-rendered subtitles or with the words burned into the image. Settle that choice before mastering: a burned-in translation remains visible throughout that version. Do not send a loose SRT to the projectionist as a substitute for the agreed package.

Read the projected line from a seat

Ask the operator to verify the package, then have the booth check the intended composition on its playback system. Read the chain-lift line and the late cue from the screen. Check accents, line breaks and the lowest line against the actual masking. Record the composition identifier, language, cue and observed fault if anything fails. A verifier can flag a missing asset; it cannot tell whether the Dutch sentence says what the deckhand meant.

If neither cue appears, check the selected composition and the referenced original before editing the SRT. If the first cue fits but the last arrives late, compare the mastering reference and playback rate with the operator. Keep the approved file intact until you know which stage introduced the difference.

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